/**
* This file is part of ORB-SLAM2.
*
* Copyright (C) 2014-2016 Raúl Mur-Artal <raulmur at unizar dot es> (University of Zaragoza)
* For more information see <https://github.com/raulmur/ORB_SLAM2>
*
* ORB-SLAM2 is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* ORB-SLAM2 is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with ORB-SLAM2. If not, see <http://www.gnu.org/licenses/>.
*/

#include "MapDrawer.h"
#include "MapPoint.h"
#include "KeyFrame.h"
#include <pangolin/pangolin.h>
#include <mutex>

namespace ORB_SLAM2
{

MapDrawer::MapDrawer(Map *pMap, const string &strSettingPath) : mpMap(pMap)
{
    cv::FileStorage fSettings(strSettingPath, cv::FileStorage::READ);

    mKeyFrameSize = fSettings["Viewer.KeyFrameSize"];
    mKeyFrameLineWidth = fSettings["Viewer.KeyFrameLineWidth"];
    mGraphLineWidth = fSettings["Viewer.GraphLineWidth"];
    mPointSize = fSettings["Viewer.PointSize"];
    mCameraSize = fSettings["Viewer.CameraSize"];
    mCameraLineWidth = fSettings["Viewer.CameraLineWidth"];
}

void MapDrawer::DrawMapPoints()
{
    const vector<MapPoint *> &vpMPs = mpMap->GetAllMapPoints();
    const vector<MapPoint *> &vpRefMPs = mpMap->GetReferenceMapPoints();

    set<MapPoint *> spRefMPs(vpRefMPs.begin(), vpRefMPs.end());

    if (vpMPs.empty())
        return;

    glPointSize(mPointSize);
    glBegin(GL_POINTS);
    glColor3f(0.0, 0.0, 0.0);

    for (size_t i = 0, iend = vpMPs.size(); i < iend; i++)
    {
        if (vpMPs[i]->isBad() || spRefMPs.count(vpMPs[i]))
            continue;
        cv::Mat pos = vpMPs[i]->GetWorldPos();
        glVertex3f(pos.at<float>(0), pos.at<float>(1), pos.at<float>(2));
    }
    glEnd();

    glPointSize(mPointSize);
    glBegin(GL_POINTS);
    glColor3f(1.0, 0.0, 0.0);

    for (set<MapPoint *>::iterator sit = spRefMPs.begin(), send = spRefMPs.end(); sit != send; sit++)
    {
        if ((*sit)->isBad())
            continue;
        cv::Mat pos = (*sit)->GetWorldPos();
        glVertex3f(pos.at<float>(0), pos.at<float>(1), pos.at<float>(2));
    }

    glEnd();
}

void MapDrawer::DrawKeyFrames(const bool bDrawKF, const bool bDrawGraph)
{
    const float &w = mKeyFrameSize;
    const float h = w * 0.75;
    const float z = w * 0.6;

    const vector<KeyFrame *> vpKFs = mpMap->GetAllKeyFrames();

    if (bDrawKF)
    {
        for (size_t i = 0; i < vpKFs.size(); i++)
        {
            KeyFrame *pKF = vpKFs[i];
            cv::Mat Twc = pKF->GetPoseInverse().t();

            glPushMatrix();

            glMultMatrixf(Twc.ptr<GLfloat>(0));

            glLineWidth(mKeyFrameLineWidth);
            glColor3f(0.0f, 0.0f, 1.0f);
            glBegin(GL_LINES);
            glVertex3f(0, 0, 0);
            glVertex3f(w, h, z);
            glVertex3f(0, 0, 0);
            glVertex3f(w, -h, z);
            glVertex3f(0, 0, 0);
            glVertex3f(-w, -h, z);
            glVertex3f(0, 0, 0);
            glVertex3f(-w, h, z);

            glVertex3f(w, h, z);
            glVertex3f(w, -h, z);

            glVertex3f(-w, h, z);
            glVertex3f(-w, -h, z);

            glVertex3f(-w, h, z);
            glVertex3f(w, h, z);

            glVertex3f(-w, -h, z);
            glVertex3f(w, -h, z);
            glEnd();

            glPopMatrix();
        }
    }

    if (bDrawGraph)
    {
        glLineWidth(mGraphLineWidth);
        glColor4f(0.0f, 1.0f, 0.0f, 0.6f);
        glBegin(GL_LINES);

        for (size_t i = 0; i < vpKFs.size(); i++)
        {
            // Covisibility Graph
            const vector<KeyFrame *> vCovKFs = vpKFs[i]->GetCovisiblesByWeight(100);
            cv::Mat Ow = vpKFs[i]->GetCameraCenter();
            if (!vCovKFs.empty())
            {
                for (vector<KeyFrame *>::const_iterator vit = vCovKFs.begin(), vend = vCovKFs.end(); vit != vend; vit++)
                {
                    if ((*vit)->mnId < vpKFs[i]->mnId)
                        continue;
                    cv::Mat Ow2 = (*vit)->GetCameraCenter();
                    glVertex3f(Ow.at<float>(0), Ow.at<float>(1), Ow.at<float>(2));
                    glVertex3f(Ow2.at<float>(0), Ow2.at<float>(1), Ow2.at<float>(2));
                }
            }

            // Spanning tree
            KeyFrame *pParent = vpKFs[i]->GetParent();
            if (pParent)
            {
                cv::Mat Owp = pParent->GetCameraCenter();
                glVertex3f(Ow.at<float>(0), Ow.at<float>(1), Ow.at<float>(2));
                glVertex3f(Owp.at<float>(0), Owp.at<float>(1), Owp.at<float>(2));
            }

            // Loops
            set<KeyFrame *> sLoopKFs = vpKFs[i]->GetLoopEdges();
            for (set<KeyFrame *>::iterator sit = sLoopKFs.begin(), send = sLoopKFs.end(); sit != send; sit++)
            {
                if ((*sit)->mnId < vpKFs[i]->mnId)
                    continue;
                cv::Mat Owl = (*sit)->GetCameraCenter();
                glVertex3f(Ow.at<float>(0), Ow.at<float>(1), Ow.at<float>(2));
                glVertex3f(Owl.at<float>(0), Owl.at<float>(1), Owl.at<float>(2));
            }
        }

        glEnd();
    }
}

void MapDrawer::DrawCurrentCamera(pangolin::OpenGlMatrix &Twc)
{
    const float &w = mCameraSize;
    const float h = w * 0.75;
    const float z = w * 0.6;

    glPushMatrix();

#ifdef HAVE_GLES
    glMultMatrixf(Twc.m);
#else
    glMultMatrixd(Twc.m);
#endif

    glLineWidth(mCameraLineWidth);
    glColor3f(0.0f, 1.0f, 0.0f);
    glBegin(GL_LINES);
    glVertex3f(0, 0, 0);
    glVertex3f(w, h, z);
    glVertex3f(0, 0, 0);
    glVertex3f(w, -h, z);
    glVertex3f(0, 0, 0);
    glVertex3f(-w, -h, z);
    glVertex3f(0, 0, 0);
    glVertex3f(-w, h, z);

    glVertex3f(w, h, z);
    glVertex3f(w, -h, z);

    glVertex3f(-w, h, z);
    glVertex3f(-w, -h, z);

    glVertex3f(-w, h, z);
    glVertex3f(w, h, z);

    glVertex3f(-w, -h, z);
    glVertex3f(w, -h, z);
    glEnd();

    glPopMatrix();
}

void MapDrawer::SetCurrentCameraPose(const cv::Mat &Tcw)
{
    unique_lock<mutex> lock(mMutexCamera);
    mCameraPose = Tcw.clone();
}

void MapDrawer::GetCurrentOpenGLCameraMatrix(pangolin::OpenGlMatrix &M)
{
    if (!mCameraPose.empty())
    {
        cv::Mat Rwc(3, 3, CV_32F);
        cv::Mat twc(3, 1, CV_32F);
        {
            unique_lock<mutex> lock(mMutexCamera);
            Rwc = mCameraPose.rowRange(0, 3).colRange(0, 3).t();
            twc = -Rwc * mCameraPose.rowRange(0, 3).col(3);
        }

        M.m[0] = Rwc.at<float>(0, 0);
        M.m[1] = Rwc.at<float>(1, 0);
        M.m[2] = Rwc.at<float>(2, 0);
        M.m[3] = 0.0;

        M.m[4] = Rwc.at<float>(0, 1);
        M.m[5] = Rwc.at<float>(1, 1);
        M.m[6] = Rwc.at<float>(2, 1);
        M.m[7] = 0.0;

        M.m[8] = Rwc.at<float>(0, 2);
        M.m[9] = Rwc.at<float>(1, 2);
        M.m[10] = Rwc.at<float>(2, 2);
        M.m[11] = 0.0;

        M.m[12] = twc.at<float>(0);
        M.m[13] = twc.at<float>(1);
        M.m[14] = twc.at<float>(2);
        M.m[15] = 1.0;
    }
    else
        M.SetIdentity();
}

} // namespace ORB_SLAM2
